Evaluation of the bond strengths of two novel bioceramic cement using a modified thin-slice push-out test model

OrthoMTA (OrthoMTA, BioMTA, Korea) and RetroMTA (OrthoMTA, BioMTA, Korea) have been newly developed bioceramic cements or tricalcium silicate cements (TCSs). The aim of this study was to examine the dislocation resistance of these two novel TCSs from radicular dentin, using a modified thin slice push-out test design that simulated canal spaces of uniform dimensions. Twenty-five single-rooted human canine teeth were used. Longitudinal slabs were obtained from each tooth using a diamond saw. Standardized canal-like holes were created using size #2 Peeso Reamer along the coronal, middle and apical thirds of longitudinal tooth slabs. The cavities were filled with OrthoMTA or RetroMTA. The slabs were kept at 37°C for 14-day in 100% humidity before push-out evaluation (MPa). Failure modes were examined with stereomicroscopy. Data were calculated using unpaired t test (P < 0.05). Location of the TCS-filled cavities did not affect push-out strengths. OrthoMTA (9.809 ± 2.176 MPa) had significantly higher push-out bond strength values than ProRoot MTA (7.103 ± 2.145 MPa) (P < 0.0001). The leaf-like bodies were seen in the fractured specimens of both TCS groups. Failure modes were predominantly adhesive in both TCS groups. It can be concluded 14-day push-out bond strength of OrthoMTA is higher than that of RetroMTA.